     (g/map->DataGranule
       (let [{:keys [Identifiers DayNightFlag ProductionDateTime
                     ArchiveAndDistributionInformation]} data-granule]
-        {:day-night (string/upper-case DayNightFlag)
+        {:day-night (get umm-g-day-night->umm-lib-day-night DayNightFlag "UNSPECIFIED")
          :producer-gran-id (->> Identifiers
                                 (some #(when (= "ProducerGranuleId" (:IdentifierType %)) %))
                                 :Identifier)

  "Contains functions for parsing UMM-G JSON DataGranule into umm-lib granule model
   DataGranule and generating UMM-G JSON DataGranule from umm-lib granule model DataGranule."
  (:require
   [cmr.umm.umm-granule :as g]
   [clojure.string :as string]
   [cmr.umm-spec.util :as util])
  (:import cmr.umm.umm_granule.UmmGranule))

(defn umm-g-data-granule->DataGranule
  "Returns the umm-lib granule model DataGranule from the given UMM-G DataGranule."

  (when data-granule
    (let [{:keys [producer-gran-id day-night crid-ids feature-ids
                  production-date-time size]} data-granule]
      {:DayNightFlag (get umm-lib-day-night->umm-g-day-night day-night "Unspecified")
       :Identifiers (let [producer-gran-id (when producer-gran-id
                                             [{:Identifier producer-gran-id
                                               :IdentifierType "ProducerGranuleId"}])
